Spin-reorientation transition of epitaxial Cu/Ni/Cu (001) structure

We have studied the spin-reorientation transition of Cu/Ni/Cu (001) system by measuring the strain, coercive field, and magnetic anisotropy of epitaxial Cu/Ni/Cu (001) films. We found that the critical thickness (tc) of Ni for the coherent growth of Ni on Cu is below 25 Å and does not occur at the peak in the effective magnetic anisotropy constant (Keff) versus 1/t curve, where t is the Ni thickness. The 60-Å Ni film, which is highly strained and shows out-of-plane magnetization, has been irradiated by 1-MeV C ions. After irradiation, the magnetization lies in the plane and the strain in the Ni film is almost released. This shows the close relationship between strain and out-of-plane magnetization in this system.